<html>

<head>
<title> Group ICA Toolbox Help </title>
<meta http-equiv="Content-Type" content="HTML, DHTML, CSS, XML, XHTML, JavaScript, VBScript; charset=iso-8859-1">
<link rel="stylesheet" type="text/css" href="../style.css">
</head>

<body>
<h4> SPM Design Matrix </h4>
<hr> 
SPM design matrix contains information about the time courses and onsets for the 
regressors. Multiple regression and correlation sorting criteria in GIFT use SPM 
design matrix to sort components temporally. The SPM design matrix filename 
selected is in .mat format. Type load filename at the MATLAB command prompt to 
view the SPM structure. GIFT uses the following fields in SPM structure:
      <dl>
      <dt> nscan </dt>  
      <dd> Refers to the number of scans. For multiple sessions, nscan should 
		look be a row vector like [110 110 ... 110]. 
      <dt> xX.X </dt>
      <dd> Contains regressor time courses of dimension m by n where m is sum of 
		scans over sessions and n (length of SPM.xX.name) is number of 
		regressors.
      <dt> xX.name </dt>
      <dd> Contains the regressor names in a cell array. Number of regressors is 
		equal to length of cell array. </dd>
      <dt> xY.RT </dt>
      <dd> Refers to the repetition time (TR). </dd>
      <dt> xBF.UNITS </dt>
      <dd> Refers to units in seconds or scans. </dd>
      <dt> Sess </dt>
      <dd> Contains information like onsets. Length of SPM.Sess is equal to the 
		number of sessions (length of SPM.nscan).</dd>            
       </dl>   
How SPM structure should look like for one session and multiple sessions are 
discussed below: 
      <dl>
      <dt> One Session </dt>
      <dd> SPM.nscan should be a number. Length of SPM.Sess structure should be 
		one. </dd>
      <dt> Multiple Sessions </dt>
      <dd> SPM.nscan should be a row vector or a single number equal to the sum 
		of SPM.nscan. Length of SPM.Sess should be equal to length of SPM.nscan.</dd>
      </dl>
      
      <b>Note: </b>GIFT pulls session specific regressors only when the 
regressor names contain the session number like Sn(1) 
right_visual_hemisphere*bf(1) where 1 after Sn( refers to the session number.
      <hr>
</body>
</html>